Gary McKinnon, the man accused by U.S. prosecutors of "the biggest military hack of all time," has won the right to a judicial review of a Home Office decision to extradite him to the U.S.

Lord Justice Maurice Kay made the ruling at the High Court in London on Friday. The Home Office had refused to halt the extradition proceedings, despite McKinnon having been diagnosed with Asperger's Syndrome, a condition on the autistic spectrum.

McKinnon's solicitor Karen Todner told ZDNet UK on Friday that she was "very pleased" about the High Court decision.

"It's a step in the right direction," Todner said. "We've got permission for a judicial review, and that shows we have an arguable case."

McKinnon's legal team applied for the review on the grounds that McKinnon's medical condition had not been taken into account by the Home Office or any UK court in deciding his extradition. If convicted by the U.S., McKinnon faces a 70-year sentence in a maximum security prison, his barrister Edward Fitzgearld QC has argued.

Todner said the review was granted on the grounds that the extradition may breach Article 3 of the European Convention on Human Rights, which states that no one shall be subjected to "inhuman or degrading treatment or punishment."

Professor Simon Baron Cohen, the Cambridge University specialist in developmental psychopathology who initially diagnosed McKinnon, said on Tuesday that McKinnon suffered the risk of "psychiatric difficulties" including depression and anxiety should he be extradited and imprisoned.

Home secretary Jacqui Smith turned down McKinnon's second appeal against extradition in October 2008, after the diagnosis of Asperger's syndrome in summer 2008.

The judicial review will not take place until after the director of public prosecutions, Keir Starmer, has decided whether to charge McKinnon. McKinnon sent a signed confession to Starmer in December admitting offenses under Section 2 of the Computer Misuse Act, in the hope of being prosecuted under UK law.

Starmer is due to give his decision in just over two weeks. If he chooses to charge McKinnon, the judicial review will not take place, as extradition proceedings will cease. Otherwise, the judicial review will go ahead "towards the end of March," Todner told ZDNet UK.